Betrayal and Guilt
by therandomer5000
Summary: Set after 'Target - April O'neil'. The brothers feel like Donnie has betrayed them by leaving them behind, after a late night lecture Donnie feels guilty. Just how far will he go to make it all up to his brothers? R&R! xx
1. Chapter 1

**Hey guys! So just a wee story that i thought up after watching an episode of tmnt this morning.**

 **Set after the episode 'Target - April O'neil'**

 **Hope you guys enjoy and... MERRY CHRISTMAS (or whatever you celebrate).**

* * *

 **Betrayal and Guilt**

The four turtles had just said goodbye to their good friend April. She had finally forgiven them for their mistake and had apologised for ignoring them.

They were all tired and their bodies ached from the fight from earlier that day, each of them were longing for their beds but the leader of the brothers felt like he needed to address something.

"Hey" he called the attention of each of his brothers but kept his eyes on Donnie. "About today"

Donnie winced, he knew he was about to be lectured.

"That wasn't cool" Leonardo frowned, "We needed you and you left us behind to go help April"

"Yeah man!" Raph growled, "you totally abandoned us! What happened to no turtle left behind?"

"I didn't mean to... I just thought... you guys had everything under control but April was all alone" Donnie bowed his head guiltily.

"She had that guy" Mikey said quietly, "She wasn't completely alone"

"That guy wasn't going to protect her, he's just some punk kid!" Donnie insisted earning himself angry glares from his brothers.

"Is that why you left!?" Leo spluttered, "just so you could... what? Win her over? Be her hero?"

"NO!" Donnie yelped in embarrassment,

"It's not a competition! He's already won, he's human you're a turtle" Raph scolded, "stop being a jealous freak!"

"You're so creepy! You left us to battle chrome dome just so you could win April?" Mikey stuck his tongue out, "she's a girl dude! Not a slice of delicious pepperoni pizza!"

"I know that! And I'm not trying to win anyone!" Donnie defended as tears of guilt pricked his eyes, "I was just trying to get her back... make up for what we did to her father... we ripped her family apart and left her alone. I just... I was just trying to help"

The brothers stayed silent for a moment.

"That's not an excuse" Leo shook his head as Raph crossed his arms. "You abandoned us... you betrayed us and left us to fight alone... anything could have happened"

"I didn't betray you!" Donnie yelped almost fearfully.

"Sure felt like it" Raph snapped, "we got our shells kicked and Leo nearly had his head cut off while you were off trying be be a Romeo for April!"

"I- I thought you guys could handle it" Donnie tried weakly, "I'm sorry"

"Bull" Raph accused.

"Raph" Leonardo warned before facing Donnie once again, "Are you a part of this team or not?"

"Yes!" Donnie insisted, hurt evident in his voice.

"Then act like it!" Leo growled before walking to his room, "goodnight"

Raphael left without another word but the slam of his door told Donnie everything. He looked over at Michelangelo who refused to look at him.

"Goodnight Donnie" he mumbled before hurrying away.

Donatello didn't sleep a wink that night, he needed to make it up to his brothers.

But how?

* * *

 **So this is only the first chapter... this could only have one more chapter or it could have several, I've not decided yet!**

 **But until then please review!**

 **Have a fun holiday season and stay safe! Xx**


	2. Chapter 2

**I left this story so I could plan it and now I'm back because I have the beginning of an idea of what's gonna happen… yeah… I hate making plans cause I can never stick to them XD.**

 **Anyway! Enjoy!**

* * *

 **Betrayal and Guilt**

Donnie didn't sleep at all that night, he was painfully aware as the hours slipped by.

He cried, screamed silently and pushed his face into the pillow to the point where he could hardly breathe.

He had messed up so badly the day before and he had no idea of how to make it right.

Michelangelo would forgive him in no time but the two older brothers would be much harder.

He flinched as he heard Leonardo walked past his room and into the dojo to begin warming up, he heard Raphael follow.

''Dojo time, dojo time, lalalalalala'' Mikey sang as he skipped, he stopped before he reached Donnie's door. He walked past hurriedly before continuing his song.

Donnie took a deep breath, he couldn't be late for training… that would just make everything worse.

He hurried out of his room and into the dojo where his three brothers were talking to the side and Master Splinter knelt under the tree. Donnie knelt before his master who looked at him in concern.

''Your brothers are not happy with you my son'' Splinter said quietly so the others wouldn't hear.

''I know father'' Donnie sighed. ''They hate me… and I don't know what to do''

''Tell me your story and I will offer any help I can'' Splinter nodded.

''Shouldn't we be starting training?'' Leo asked from the side of the room.

''Not yet my son'' Slinter called over. ''All minds must become one for our training to be successful, Donatello is needing some assistance with that this morning''

Donnie felt the burn of glares on his shell and tried not to show his guilt.

''Begin'' Splinter said quietly.

Donatello told him of how he left his brothers for April, he told him every detail of last night before having to stop as his voice was breaking.

''I see… this is most worrying'' Splinter shuddered. ''My brother and I fought because of a girl and now you four are doing the same thing''

''yeah except there's three of them so they'd definitely succeed in killing me''

''Donatello!'' Splinter scolded before closing his eyes. ''It will not come to that, you boys are different''

''How do I get them to forgive me Master?'' Donnie pleaded.

Splinter sighed.

''I am afraid that is something you have to find out for yourself''

Donnie bowed his head in defeat.

''Chin up Donatello'' Splinter smiled gently. ''As long as you try your hardest nobody can fault you''

Splinter stood up.

''Come my sons'' He called. ''Kneel before me so training can begin''

The brothers did as they were told.

Donnie frowned. He would have to try super hard in training today to prove to his brothers that he will fight for their approval.

''We have lost a lot of time today so we will just have a simple sparring session. Leonardo you will be sparring against Raphael, Michelangelo against Donatello'' He waited for the brothers to get into position. ''Hajime''

Leo and Raph were quick off the mark while Mikey and Donnie started awkwardly.

Donnie made the first move much to Michelangelo's confusion.

''Why're you trying so hard?'' Mikey asked.

''I need to prove myself to you guys… that means I can't make any mistakes'' Donnie replied, ''I need to show I'm sorry''

Mikey raised an eyeridge before frowning

''You really think being good at training is gonna help with that?''

Donnie felt disheartened at Mikey's miffed tone.

''It might''

Donnie saw that Leo and Raph were finished and watching them with emotionless masks. He decided to try and end it himself.

He saw Mikey rush towards him and charged himself, he tried to flip over and land so he could kick Mikey's feet out from under him.

But misjudged his landing and fell straight onto his wrist and nearly cutting his neck on the weapons rack.

Mikey stared at him with wide eyes as he leapt to his feet holding his wrist.

''I'm ok'' he blushed.

''That's enough for today'' Splinter sighed, he watched as Donnie rushed out of the dojo and into his lab.

''Dudes'' he overheard Mikey talking to his brothers. ''He nearly sliced his neck open!''

''What was that all about?'' Raph asked in surprise.

''He said he wasn't gonna make any mistakes and that he was gonna try hard at everything to prove himself to us'' Mikey explained.

''That's stupid'' Leo rolled his eyes but the worried look was still evident.

''D's gonna get himself killed if he keeps doin' stuff like that'' Mikey bit his lip nervously.

Splinter shook his head sadly, the three were growing concerned yet did not seem to be willing to forgive. Splinter could only hope that they were wrong.

Later on in the day the three turtles were watching tv when Donatello left the lab with bandages on his wrist, he looked at them for a moment before heading to the bathroom.

''His wrist must be bad'' Leo whispered. ''I hope it's not broken''

The other two nodded.

''My sons'' Splinter calmly walked over to the brothers. ''Donatello has told me what has happened and while what he did was wrong he is still your brother. Do not punish him for too long, I worry what lengths he will go to try and gain your forgiveness.''

They looked at one another as Donatello left the bathroom.

''How is your wrist my son?'' Splinter called.

''It's um… It's fine Master'' Donnie shuffled awkwardly as his brothers refused to look at him. ''Just a little bruising on the bone… kind've twisted it… it'll be fine''

''Do not work too hard'' Splinter nodded. ''You must rest, you look as if you haven't slept all night''

Donnie faltered before nodding, he headed to his room to try and sleep.

Splinter went to the dojo with worry in his heart and memories of his past playing over in his mind.

* * *

 **Please Review xx**


	3. Chapter 3

**No work until Thursday! Yay! So I'll be doing more writing today!**

 **Something will be cleared up for Glazier Blue and Guest in this story because it occurred to me that some people aren't quite understanding what's going on, which is fine because this criticism was constructive rather than nasty which I really appreciate.**

 **That will be cleared up in the chapter but trust me, the brother's will not forgive Donnie because they feel sorry for him. I promise that is not what's going to happen because that would be a really sucky ending.**

 **So don't worry! I'm really not that predictable ;)**

 **Now that that's cleared up.**

 **Enjoy x**

* * *

 **Betrayal and Guilt**

The next day was awkward to say the least.

Donatello wasn't allowed to train because of his injury and was forced to rest his wrist by watching tv with no access to his lab.

He felt ashamed and embarrassed, even somewhat annoyed.

Why was he bothering to prove himself, his brothers were being so strict over one simple mistake.

So he saved April, what else was he supposed to do when she was in danger exactly?

He couldn't just leave her to get hurt or killed.

He loved her.

The day continued with mostly silence and everybody avoiding each other.

But then night came.

''We're going out for patrol'' Leo announced as he sheathed his katanas,

''Donatello will be joining you'' Splinter added as he walked into the room and glanced at Donnie, ''after all it is his wrist that is injured not his legs''

''but what if we get into a fight?'' Mikey asked worriedly, he knew Donnie wouldn't be able to use his staff effectively.

''No need to worry about that'' Raph grumbled. ''He'll probably run off to April's and leave us to it''

Donnie frowned but sheathed his bo.

''C'mon guys'' Leo sighed. ''We're wasting time''

The four brothers rushed out of the sewers and into the night leaving their father to sit and think.

Splinter had demanded Donatello join his brothers in hopes of them talking and bonding, he hoped his son would be able to gain their forgiveness.

Out on the rooftops the brothers were running silently, it had been pretty quiet so far.

''Can we stop?'' Mikey panted.

''We've only just started'' Leo shook his head. ''We need to get half way before we stop or we'll be out here forever''

''Please'' Mikey begged, his two older brothers ignored him, he looked to Donnie who would normally take his side but saw his brother was deep in his own thoughts. Mikey hated being cold towards a brother for too long so decided to include Donnie into their conversation. ''Hey Donnie''

Donnie looked over at Mikey in surprise, he hadn't expected his brother to talk to him.

''Yeah Mikey?'' He smiled genuinely causing Mikey to grin.

''How's the wrist? You missin' your lab?'' Mikey chuckled good naturedly.

''It's a little swollen but not too painful'' Donnie replied honestly. ''And yes… I am missing it''

Mikey laughed a little and noticed his other two brothers were trying to hide their smiles.

''I can't believe you actually watched tv all day!'' Mikey commented. ''You've not done that in years''

''I know… I could feel my brain cells dying watching those cartoons'' Donnie shook his head. ''That documentary saved me''

''What documentary?'' Mikey asked, he hadn't noticed it.

''It was on while you guys were in the kitchen,'' Donnie blushed, he knew they did it to get away from him. ''It was about the history of Japan, it talked about their culture, art and how it has all changed over the years… it was really interesting… you guys would've liked it''

The brothers felt bad because they knew it was true.

They all would have enjoyed learning about their father's home country but they had decided to get away from Donnie instead.

''I'm sorry we missed it'' Leo frowned. ''That does sound pretty good''

They continued in silence until they reached halfway where they stopped for a break.

They did a few stretches and katas before sitting down for a few moments.

Everything was silent.

Until suddenly a hoard of foot ninjas appeared on the rooftops around them.

''Guys! Into formation'' Leo called. ''Donnie, don't you dare fight. You need to rest your wrist''

Donnie gaped as his brothers began the fight trying to keep the ninja away from him.

These ninja were clearly in training as they were dropping like flies.

''I'm not just gonna sit back!'' Donnie frowned. ''I can help, I'm not that badly injured''

He leapt up and took out his bo.

He needed to prove he was strong and wouldn't back out of a fight, he would show his brothers that he'd never leave them to fight alone.

''Donnie!'' Leo growled. ''I told you to stand down!''

''I can handle them Leo!'' Donnie argued as he fought the few that had gotten past his brother's defences.

He mainly used his left hand as his right was actually pretty painful to use, it was actually quite effective until a ninja with a katana appeared in front of him.

This ninja was pretty inexperienced but determined, he swung repeatedly at Donnie so the poor turtle would need to use both hands to protect himself.

He grit his teeth against the pain as the katana blade cut the bandages around his wrist so they fell to his feet.

Now his wrist was unsupported and actually looked a lot worse than it did this morning, he groaned inwardly before swinging his bo into the ninja's head. Hard.

The ninja was knocked unconscious leaving Donnie panting.

''You idiot!'' Leo scolded as he finished off his last opponent. ''I told you to stand down now look at your wrist!''

''It's fine'' Donnie insisted as he tried to hide it.

''What were you thinking!?''

''I was helping you fight'' Donnie insisted. ''Like I'm supposed to.''

Mikey frowned before sighing angrily.

''Is this you trying to prove yourself again?'' He grumbled. ''Didn't you see how that went the last time?''

Donnie blushed.

''Are you kidding me?'' Leo stared at Donnie with fire in his eyes. ''This is why you fought? To prove yourself?''

''You said I needed to show you that I'm part of the team! That I wouldn't just run off and sit back and watch!'' Donnie replied defensively.

''You don't get it do you'' Leo deadpanned, he calmed himself. ''We're not mad at you for saving April, anyone of us would have done the same thing. We're mad at you because you left us behind without a second thought! As soon as April called you left, you could've helped us first and then all of us would have gotten to April in time. The same thing happened when we were in the Kraang's underwater base, April called you to tell you she was being chased by Karai and you wanted to abandon the whole mission.''

Donnie winced, he hadn't realised how often this had happened.

''We can't trust you'' Raph shook his head in frustration, ''What if we were fighting the Shredder and April needed your help, would you leave us then?''

''No!'' Donnie gasped. ''The Shredder is completely different! He's stronger than that robot thing!''

''Chrome dome was super strong once he was charged'' Mikey stepped forward. ''But you had the skills to shut him down before he could even go after April, then we could've saved April together from Karai instead of having to fight two strong enemies at once''

''I didn't think about that'' Donnie bowed his head.

''Exactly'' Leo turned away from Donnie. ''That's the problem… once April needs help you'll just leave us without even thinking about us… we can't rely on you''

Donnie suddenly felt very sick.

Was Leo right? Would he really leave his brothers to die without a thought if April needed him?

''Let's go home'' Leo sighed quietly. ''You need to sort out that wrist''

Leo, Raph and Mikey began running as Donnie stared at his hands, he felt terrible and sick with himself.

What was he going to do?

* * *

 **Please Review x**


	4. Chapter 4

**Here's the next chapter! enjoy x**

* * *

 **Betrayal and Guilt**

Splinter stood up hopefully as his four sons returned home, he frowned when Donatello went straight to his lab while the other three flopped into the pit looking exhausted.

''Did you have a good patrol my sons?'' Splinter asked calmly.

''It was good until the foot showed up'' Raph grumbled.

''The foot? Was anyone injured?''

''No'' Leo replied. ''They weren't good fighters… but Donnie did agitate his wrist by getting involved''

Splinter raised an eyebrow at this.

''Why did he fight when he knew he was injured?'' He asked but felt like he already knew the answer.

''Cause he's an idiot'' Raph crossed his arms. ''Wanted to prove himself''

''Were you not the same when your brothers kept you home for your anger issues?'' Splinter asked. ''As were you Leonardo when you first met Karai''

Said brothers squirmed a little as Mikey frowned.

''I've kind've forgiven Donnie'' He admitted. ''He didn't mean to leave us… besides he's learnt his lesson''

''You can't stay mad at anyone can you?'' Raph glared at his little brother.

''It is not good to hold grudges Raphael… especially when it comes to family'' Splinter corrected.

''I'm not holding a grudge'' Raph sat up. ''I just… what makes April more important than us?''

''So you are jealous?'' Splinter looked over his three sons before softening his gaze. ''You three are worried that your brother will one day leave you for April permanently, you worry his affections for April will hurt him in the end due to him being so different''

The brothers didn't look at him.

''I can tell you now my sons, Donatello values family more than you know. As for his affections… they may or may not be misplaced but no matter what happens you cannot hate him for falling in love, it is not something we can help after all'' Splinter smiled gently as he watched Donnie leave the lab and head straight for bed.

''You're right Master'' Leo piped up. ''We're being too hard on him… it's just… it's worrying how…''

''I understand my son'' Splinter nodded. ''I doubt he understands his actions anymore than we do… now, go to bed my sons… I believe you will feel much better in the morning''

The brothers nodded and headed to bed.

The next morning Donnie headed straight for his lab while his brothers trained, he still felt guilty and confused.

For the three brothers training took forever, they needed it to end so they could see their brother.

''Hey guys'' Came a feminine voice from the entrance. It was April.

''Hey April'' Donnie smiled weakly as he wandered out the lab, ''the guys are training just now, what do you need?''

''Actually… I need to speak to you…'' April bit her lip nervously, ''There's something I have to confess''

The four mutants in the dojo peeked out to see the two teens looked nervous and confused.

''What's she gonna say?'' Mikey whispered.

''SH!'' Leo and Raph hissed. They all turned their attentions back to the couple.

''What's wrong?'' Donnie asked in concern.

''Nohing it's just…'' She took a deep breath, ''Donnie… I really like you… ever since you saved me from the kraang I've kinda had a crush on you and I've been too scared to admit it''

The five mutants gaped at her, was this real?

''I just em… I just wanted to know… how you feel?'' She blushed.

Donnie stared at her, he couldn't believe it… his dream girl just admitted to having feelings for him.

He was about to tell her the truth when he suddenly paused.

No… if he started dating April… how would this add to his brothers' annoyance? This would only prove their point further.

Did he really have to pick between April and his brothers… should he really be thinking this hard about it?

He needed his brothers to forgive him, he couldn't say yes to April…

How could he put this delicately?

''April'' He breathed. ''I can't believe it… I'm sorry''

April's expression dropped at those words, his family frowned.

What was he doing?

''I can't believe I'm about to say this… I've wanted this for so long…'' Donnie swallowed dryly. ''But I can't go out with you… I want to… believe me I do but… it wouldn't be right…''

April came to her own conclusion.

''So… you like me? But… you're having the same thoughts about the problem… cause like… I'm a human and you're a turtle mutant so… it probably wouldn't have worked out… I mean… there's so many differences…'' April shuffled before smiling gently up at Donnie. ''You're right… of course you're right… Thanks for being so nice about it''

''No problem'' Donnie choked through the pain in his chest.

''At least now we can be close friends'' April nodded. ''There's nothing weird between us right?''

''No! of course there's nothing weird'' Donnie waved her off, ''We're good''

''Great'' April bit her lip again, her first rejection… ouch ''I'll see ya later''

She hurried out of the lair leaving Donnie behind.

''Oh my god'' Mikey whispered. ''That did not just happen did it? Please tell me he didn't reject her because of us''

''I think he did'' Raph winced.

''He has no idea that we've forgiven him… he just rejected April!'' Leo grabbed his head with both hands in distress. ''She liked him back and he said no!? All because of us…''

Splinter left the dojo and stepped closer to Donnie.

''Are you alright Donatello?'' he asked gently.

''Y-yeah'' Donnie blushed as he scrubbed at his eyes. ''Why wouldn't I be…''

''My son-''

''Tell the guys I don't want their forgiveness anymore'' Donnie stepped away from his father and towards the lab. ''I'm done… if they're gonna be this mad about it then I give up''

He walked into his lab and shut the door softly, locking it in the process.

The three brothers came out of the dojo and headed towards the lab only to be stopped by their father.

''He is hurting'' Splinter sighed softly. ''Leave him be for now… once he has calmed down tell him the truth… in time he will understand''

The brothers nodded guiltily, they shouldn't have been so pig-headed… if only they had apologised before training, everyone would've been happier.

* * *

 **Please Review x**


	5. Chapter 5

**There's some action after this chapter! So enjoy the fluffiness for now!**

* * *

 **Betrayal and Guilt**

Donatello sat hunched over his desk with his head in his arms, he'd been crying since he got in and just couldn't seem to stop.

He couldn't believe his luck.

April loved him but he had to reject her for three brothers who refuse to forgive him for making a mistake.

How could he have messed up this badly? What made him deserve this?

Was what he did that bad?

Outside of the lab his family were worried for him, he hadn't come out all day and it was nearing dinner time. Donatello hadn't eaten a single meal yet.

But they didn't want to intrude knowing how upset he must feel.

They couldn't believe their bad timing, just as they were going to forgive him April comes along and messes it all up.

They may have forgiven Donnie but would he forgive them?

Master Splinter stood up and went into the dojo to meditate, he couldn't stand sitting around any longer.

Leo began to pace in the pit, they all wanted Donnie to come out feeling ok again.

It wasn't until night time that the lab door opened and Donnie came out, the brothers frowned at his appearance.

He was pale and tired looking, his eyes were red and puffy from crying and he looked just plain miserable.

''Donnie'' Leo began as Raph and Mikey leapt up.

''Save it'' Donnie muttered. ''I'm not interested anymore''

''No'' Leo coughed, ''Please just hear us out''

Donnie hesitated but sat down, he looked at each of them sceptically.

''What's up?'' He asked.

''We wanted you to know we forgive you and that we're sorry about April'' Leo admitted, Donnie scowled at his three brothers and leapt up.

''Are you kidding me!?'' He growled. ''You're forgiving me out of pity!? You waited until I had to say no to going out with my crush before you could forgive me? Well I don't want your forgiveness anymore!''

''Donnie! You don't understand'' Mikey yelped in alarm.

''What? I don't understand what?'' Donnie demanded, all his energy seemed to leave him and he flopped back down onto the padded bench, he bowed his head miserably.

''We forgave you last night… we talked to Splinter and realised we were being too hard on you'' Raph rubbed the back of his neck, he looked to Leo to continue.

''Master Splinter made us realise that… we were so mad because we felt threatened… we're not used to having someone else around and we felt like we were losing you to April'' Leo admitted, Donnie looked up at them in confusion. ''We were afraid of you getting hurt or leaving us for April that… we wanted to teach you a lesson, we took it too far''

''We were gonna apologise and forgive you this morning after training'' Mikey sighed. ''We were too late''

Donnie stared at his brothers and gaped like a fish.

Were they telling the truth?

He could see their guilt and realized they were telling the truth.

''Oh'' He breathed.

''We're so sorry'' Mikey bowed his head.

''It's ok'' Donnie sighed. ''This was all just…. Bad luck…''

The brothers shuffled awkwardly.

''You guys should know that nobody is more important to me than this family'' Donnie told them sternly. ''I may rush off to help April occasionally but I would never leave you for her permanently''

They nodded.

''We know that…'' Raph nodded sadly. ''You should go tell April the truth of why you rejected her''

''Yeah'' Mikey smiled. ''Maybe you still have a chance?''

''I don't think so'' Donnie sighed. ''Didn't you hear what she said… she told me it wouldn't work out anyway''

''She doesn't really believe that'' Leo frowned gently, ''It was just her way of acting nonchalantly, she loves you''

Donnie stayed silent, he couldn't just admit it all to April now… she'd be really upset if she found out the truth.

Donnie jumped when he felt a pair of arms around him, he smiled at Mikey and hugged him back. The other two brothers were quick to join as Donnie began to cry again.

He was relieved he had his brothers back yet his heart hurt from rejecting April, he hoped this pain was only temporary.

* * *

 **Yay for forgiveness! Please Review and I might post the next chapter today ;)**


	6. Chapter 6

**Hey guys! I know I said I'd upload this sooner and obviously I didn't so sorry! The reviews were really nice and I feel bad for forgetting... anyway...**

 **Enjoy x**

* * *

 **Betrayal and Guilt**

Leonardo stood by the turnstiles as he sheathed his katanas, he was waiting for his brothers so they could go on patrol.

He had a bad feeling in his gut but figured it was just because his brother was still so depressed.

''MIKEY!'' Raph yelled as he chased Mikey to the turnstiles they both stopped in their tracks at the look their leader gave them.

''Enough'' He warned.

Raph rolled his eyes impatiently.

He was just about to complain when he noticed Donatello heading towards them.

''Sorry'' Donnie cleared his throat awkwardly, ''I didn't mean to take so long''

''Don't worry about it bro!'' Mikey tried to cheer Don up, ''The longer you take the more time we get to spend in the warm!''

Donnie chuckled a little at that.

''Let's go guys'' Leo nodded happily, he was glad Mikey was so dedicated to making Donnie feel better.

The four turtles ran over the rooftops for about half an hour before stopping.

''um'' Mikey winced from his side of the roof. ''Maybe stopping here isn't a good idea.''

The brothers looked over the edge to see April, Irma and Casey walking down the side walk.

Donnie frowned, April looked troubled.

''C'mon Red'' Casey grumbled rudely. ''I thought we were going to the movies alone''

''We are'' Irma smirked.

''I meant just me and April'' Casey glared at her but Irma didn't seem overly offended.

''What? Like a date?'' She scoffed. ''Sorry but April's interested in somebody else''

''Really?'' Casey looked surprised. ''Who?''

''Some guy called Donnie'' Irma grinned, April went bright red and stared at Irma.

''How did you-?'' April frowned.

''Oh please April, it's so obvious.'' Irma laughed. ''I looked at your phone and his name has hearts on both sides!''

''You looked at my phone!?'' April snapped. ''Irma!''

''Sorry April'' Irma smiled apologetically, April shook her head.

''Who's Donnie!?'' Casey interrupted. ''I'll kill 'im!''

''Shut up Casey'' April mumbled. ''He's not interested in me anyway''

''Well I am!'' Casey grinned. ''And I think we should go on a date!''

''No'' April deadpanned. ''Sorry but I'm not interested''

Donnie frowned guiltily, April seemed so unhappy… That guy wasn't her boyfriend.

''What an asshole'' Raph shook his head in disgust, ''like April would be interested in him''

''Let's go'' Leo straightened up. ''We have a patrol to finish''

They followed their leader awkwardly, Donatello was deep in thought as they ran.

All he could think about was April.

''Guys!'' Leo hissed as he noticed something in the alley. ''Kraang''

The brother peeked over the roof to see four Kraang droids go through a garage door at the end of the alley.

''C'mon'' Leo motioned for his brothers to follow him, together they leapt through the garage door before it closed.

They'd expected to see just the regular concrete walls and floor of your average garage but instead they found themselves in a chrome hallway.

''Woah!'' they all gaped.

''This is new'' Donnie frowned all thoughts of the past few days completely out of his mind. ''The Kraang must be up to something huge to build something like this''

''But what?'' Leo looked at Donnie hoping for an answer but Donnie shook his head.

''I don't know''

''Whatever they're doing's gonna be bad'' Raph huffed. ''Lets just find whatever thing they're doing and break it!''

''Yeah!'' Mikey cheered earning a grin from Raph and dirty looks from Leo and Don.

''Stay close ninjas'' Leo whispered. ''Full stealth mode''

The brothers nodded and followed the eldest brother.

They'd been walking along chrome corridors for ages and each room they had come across had just been empty of all kraang and clues.

That is until they came up to a massive steel door.

They looked through the window and stared in horror.

Kraang filled the room and in the centre there was a massive pulsating portal, the Kraang were staring at it as if waiting for something to emerge.

''That doesn't look good'' Leo looked at his brothers.

''what the hell is coming out of it?'' Raph blanched. ''It's gotta be huge to need a portal that size!''

''Maybe it's just that rock guy?'' Mikey suggested. ''He was big''

''No way'' Done shook his head. ''It's gotta be something a lot more dangerous than him… either way we gotta shut it down''

''Right'' Leo nodded as he looked through the window again. ''there's a huge control panel over on the right hand side, think you can shut it down Donnie while we distract the Kraang?''

''Sure'' Donnie nodded. ''But there's a lot of Kraang in there''

''Yes but we can be Very distracting'' Mikey smirked mischievously.

''Lets go'' Leo commanded as they tried to bust through the door only to find it locked, Donnie picked at the locked and suddenly it swung open.

The Kraang spun around just as three of the brothers rushed in and began the fight, Donatello went straight over to the control panel and threw the Kraang without suits across the room.

''Let's see'' Donnie began his work and soon and a good understanding of what he needed to do, there were two switched with two codes for this side of the portal.

He only hoped that there wasn't two more on the other side.

The three brother fought diligently and managed to defeat half the room of kraang while keeping an eye on their brother.

''How much longer Donnie?'' Leo called over.

''A few seconds!'' Donnie grinned triumphantly as he finished the second code and flicked the second switch.

The portal flickered as lightning burst out from within it, Donnie stared in horror as it went a sickly green/blue colour.

''Uh… Donnie! Why isn't it gone?'' Raph yelled.

Donnie shook his head as two floating kraangs head towards him from under the portal.

There were more switches.

''There's more switches'' Donnie stood up straight and stared at the portal. ''But…. They're on the other side''

''What do you mean other side?'' Leo yelled.

''I have to go through the portal to switch it off'' Donnie gulped as the lightning zapped half of the remaining Kraang causing them to explode.

''No!'' Mikey yelped. ''You can't''

''You'll be stuck in dimention X if you do that!'' Leo shook his head. ''You won't even be able to breathe''

''I have to'' Donnie frowned.

He was scared, he couldn't die!

But why shouldn't he?

He was miserable now, he had rejected April, things were still awkward with his brothers and he wasn't a good ninja, he didn't fit in with his own family.

Could Splinter handle losing another child?

Yes… he was useless to his father anyway.

His sacrifice would make up for everything he ever did wrong.

He had to do it.

''Guys'' Donnie called as he prepared himself, his brothers looked over at him. ''Take care of yourselves ok?''

''What?'' Raph frowned before cottoning on. ''No… DON'T YOU DARE!''

Donnie ran forward and used the floating Kraangs as steps to get up to the portal.

''I love you guys'' He called as he reached the last step.

''DONNIE!'' The brothers called as Donnie dived into the portal. ''NOOOOO!''

* * *

 **Please Review xx**


	7. Chapter 7

**This is short and late! I'm so terrible! Honestly this was written ages ago and I thought I had posted it up, I've been so busy lately that I just completely forgot about my stories.**

 **So, sorry! and please enjoy! x**

* * *

 **Betrayal and Guilt**

'' _DONNIE!'' The brothers called as Donnie dived into the portal. ''NOOOOO!''_

The three brothers rushed towards the portal only for it to be blocked by the remaining kraang.

''LET US THROUGH!'' Raph snarled as he slashed the Kraang with his sai.

''DONNIE!'' Mikey called hoping his brother could hear him through the portal.

Suddenly the portal began to shrink and shudder, it made a strange wheezing sound.

The brothers leapt over the Kraang and towards the portal only for it to close before they could go through.

''NO!'' They yelped as they fell to the ground.

''D-Donnie'' Mikey gasped as tears fell down his face, there was a heavy silence as the brothers stared at the empty space.

''H-He's dead'' Raph stuttered. ''He's actually d-dead''

''He might not be'' Leo tried. ''We might be able to bring him back?''

He looked at his two younger brothers but they just continued staring into space.

Suddenly Leo was grabbed from behind and hoisted to his feet, he yelped as he was dragged backwards roughly.

''Leo!'' Raph growled as he and Mikey leapt to their feet with their weapons out.

Leo struggled against the Kraang's grip but it was no use, he flinched when a gun was held pointing to his head.

''You've already taken one of our brothers'' Raph growled emotionally as he and Mikey stepped forward threateningly. ''You will not hurt another.''

''Surrender'' The Kraang droid bleeped. ''Or the one known as Leonardo will be that which is known as dead''

The two younger brothers grit their teeth but did as they were told. They allowed the Kraang to capture them.

Leo bowed his head as they were taken to a cell together, they've never given up before…

They were thrown into their cell before the door slammed shut, the door was just one big purple wall which caused their hearts to squeeze.

''Guys'' Leo sat up. ''You shouldn't have done that''

''We couldn't let you die Leo'' Mikey whimpered as he hugged his eldest brother. ''Not after… Donnie''

Leo hugged Mikey tightly as he cried.

''We can't give up'' Leo croaked. ''Donnie could still be alive''

''Stop it Leo'' Raph growled. ''Stop tryin' to give us false hope… Don's dead… it's over''

''It's not''

''Yes it is'' Raph snapped before sighing. ''We can't carry on with only three of us… we're a team''

''it's not just the three of us'' Leo frowned. ''Donnie's alive… I know he is, I can feel it''

His brothers didn't look convinced.

''If you give up then Donnie's gonna be trapped with the Kraang for the rest of his life… he's all alone over there and god knows what's happening to him'' Leo shut his eyes. ''We can't abandon him… he's our brother''

''You say you can feel him?'' Mikey sniffed as he looked up at Leo.

''Yes'' Leo nodded. ''And I would feel it if he died, he is alive right now but that could change if we don't try to save him''

''I believe you'' Mikey smiled. ''You're our leader… you would know if one of us was hurt, you always do''

Leo nodded and hugged Mikey.

''I guess you're right'' Raph nodded. ''He's gotta be alive… and we'll save him''

Leo grinned as Raph joined the hug.

''But how?'' Mikey asked. ''We're stuck here and none of us are smart like Donnie''

''We'll work something out'' Leo frowned determinedly, ''I promise.''

Leonardo stared at the purple door and took a deep breath, he had a plan.

He only hoped it would work.

* * *

 **I'm sorry this is so short but hopefully I'll have time soon to write the next chapter!**

 **Please Review in the meantime to remind me to do it?**


	8. Chapter 8

**Here's the next chapter finally! enjoy x**

* * *

 **Betrayal and Guilt**

The brothers had finally worked out a plan to get out of their cell.

It took a lot of thinking and hits on the head but eventually they came up with something.

''AHHH! MY STOMACH! OH AH! OWWWWW!'' Mikey wailed loudly.

They had definitely came up with… something.

''This is never gonna work'' Raph groaned to Leo who quickly shushed him.

''It's all we've got, just look worried ok?''

Raph shook his head but perked up when a single kraang droid appeared in front of their cell.

''What is that which is wrong with the turtle known as Michelangelo?'' It asked.

''He's really sick!'' Leo gushed worriedly as Mikey pretended to writhe in pain. ''He needs help''

The kraang turned to leave.

''Wait! He could die!'' Raph called causing the Kraang droid to pause.

''The one known as Michelangelo is that which is known as useless to the us who are known as the kraang'' the droid deadpanned.

''HE COULD BARF!'' Leo yelped in panic earning himself a confused glare from Raph.

The kraang turned urgently to look at Mikey who proceeded to pretend to heave.

The droid was quick to unlock the cell, the turtles felt a slight pain in their hearts as the purple beam died.

As soon as the kraang entered the cell Leonardo killed it to prevent it setting off any warning.

''Yeah! I knew it would work!'' Mikey cheered as he leapt up. ''Nice one Leo!''

''Why'd you say he was gonna barf?'' Raph smirked.

''It worked didn't it?'' Leo replied testily. ''C'mon''

The three turtles left the cell quickly and headed up the corridor.

''Where are we goin' Leo?'' Mikey frowned.

''Yeah, the Portal room's in the other direction!'' Raph snarled but didn't stop.

''We can't just head in there blindly'' Leo replied. ''We need to find something we can use to breathe when we get to dimension x''

''But Donnie didn't have anything and you said he was alive'' Mikey pointed out,

''We don't know the circumstances, better safe than sorry'' Leo nodded.

''Where are we gonna find oxygen that we can just take in here? The kraang don't need it'' Raph asked.

''Donnie told me a while back that the kraang would have a load of oxygen tanks around here to test on, they needed to find a chemical that could turn it into kraang air'' Leo explained as they turned the corner. ''We need to find those tanks.''

''Where would they be?'' Raph asked hoping Donnie might have told Leo that too.

''In the lab'' Mikey grinned as he rushed off ahead. ''It'll be in one of the big labs! C'mon, I bet I know which one!''

Raph and Leo shared a look but followed their brother anyway.

They twisted and turned through a couple of corridors to find Mikey disappearing through a door, they followed him into a huge lab that seemed completely empty.

''Nice one Mikey'' Raph huffed. ''There's nothing here.''

''This is one of the labs they store stuff in, they have ones just like it in dimension x'' Mikey replied as he started stroking a random wall. ''One of these walls is hiding a secret storage bit, we'll find oxygen tanks in there''

Leo and Raph watched their baby brother as he stroked each wall.

''He's insane'' Raph sighed. ''There's no way''

Mikey cheered as his wall opened.

''You really don't give him enough credit'' Leo smirked as he walked towards Mikey who was bouncing excitedly.

Raph shook his head in disbelief but headed towards the wall.

''Nice one Mikey'' Leo praised as he stared at the wall of canisters. ''Look at all these oxygen tanks!''

They each grabbed one and froze.

''How are we gonna breathe this?'' Raph asked. ''It's not like we have those mask things''

''No'' Leo nodded before pulling some tubes out of the wall. ''But we can fashion breathing tubes, I saw Donnie do this once''

Leo worked hard to follow how he remembered Donatello doing it and after a few tries he got it right.

He sorted all three tanks and together they headed for the portal room.

''These are heavy!'' Mikey complained. ''I don't wanna carry it''

''Too bad'' Raph grumbled.

They arrived at the portal room to find that it was back up and running.

''Donnie's sacrifice was for nothing'' Leo growled. ''Let's do this''

The three turtles barged in and ran straight for the portal, the Kraang droids were quick to try and shoot them down but to no avail.

Within a matter of minutes they were through the portal.

''WOAH!'' Mikey grinned as his oxygen tank floated just behind him, ''Cool! I don't have to carry it anymore!''

''Careful'' Leo warned as he held his tube in place, ''we can't lose these or it's game over.''

They looked around to see they were standing in a dark lab with only the portal as a source of light.

''C'mon'' Leo nodded but Mikey took the lead, they headed out the door only to find themselves outside.

''A standalone lab'' Raph observed.

''I guess they don't have to hide anything around here'' Leo nodded. ''It can all be out in the open…''

They stood in awe for a moment as they adjusted to the weirdness of dimension x.

''Well, we're here'' Raph growled. ''But where's Donnie?''

''I-… I don't know'' Leo stuttered. ''He's only been gone for a couple of hours, he couldn't have gone far?''

''Try a couple of years bro'' Mikey sighed sadly. ''Time moves differently around here''

''Shit'' Raph gasped. ''I forgot about that! It might've been more than two years! Who knows how long it's been!''

''It's been two years, eleven months and 25 days actually'' Came a familiar yet different voice from behind. ''But who been counting?''

The three brothers spun around to see-

''Donnie'' Leo gulped as he took in his brothers appearance. ''god…''

Donatello wasn't too different from how he had been before he had left.

He looked tired and his clothes were a little tattered, he even had a few cuts and scars on his plastron and arms.

But there was one thing that told them something huge had happened while Donatello had been stuck here.

On both legs, just under the knee were running blades instead of shins and feet.

The entire lower legs were gone and replaced with hand-made running blades.

''Donnie… what happened!?'' Raph gasped. Donatello took a couple of steps towards them with a gentle smile upon his face.

''It's good to see you guys too'' He chuckled.

At that his brothers melted, they dashed towards him and hugged him desperately.

''We thought you were dead'' Mikey choked out as he tried to keep himself from crying.

Donnie said nothing but continued to hug them.

He noticed they had oxygen tanks attached to them instead of his homemade breathing tubes, he leapt back.

''How much oxygen do those have?'' he asked worriedly.

''I-I don't know, why?'' Leo asked in alarm.

''Oxygen is used up pretty quickly!'' Donnie explained as he took a closer look, he frowned in concern.

''You guys can't have more than four hours of oxygen left'' He gulped. ''Please tell me that whatever portal you used to come here is still open''

''Yeah, it's the same one you jumped through'' Raph replied.

''Good, you guys have got to get back to earth before your oxygen runs out!'' He froze at his brothers expressions.

''Us? You're coming too right?'' Leo frowned. ''We came here to bring you back…''

Donnie sighed and bowed his head.

''I don't know that I can… th-the kraang did stuff to me while I was here,'' He shuddered. ''They've changed me…''

''Tell us.'' Leo demanded. ''Tell us what they did and we'll go from there''

Donnie nodded, they only had so long to breathe.

Arguing would be pointless at this stage.

''Fine'' He nodded. ''But you guys won't like it''

He took a deep breath and began his story.

* * *

 **We'll find out what happened to him in the next chapter! Also if you don't know what running blades are they're what the Paralympic runners have.**

 **Please Review x**


	9. Chapter 9

**Hey! I'm updating so soon! It's a miracle! Enjoy xx**

* * *

 **Betrayal and Guilt**

When Donatello had first fallen through the portal he had the intention of flicking those last two switches.

When he hit the floor while holding his breath he noticed there were only five Kraang in the room, he thought shutting down the portal would be an easy job.

It wasn't.

As soon as he stood up those Kraang were on him like a rabid dog to fresh meat.

They weren't shooting, they were grabbing and trying to restrain him. Donnie scanned the room and noticed a huge vehicle heading towards the portal. A space truck of some sort.

That was the portal's purpose. To allow that truck through to deliver whatever dangerous load it was carrying.

Donatello had quickly leapt away from the Kraang, he knew he wouldn't be able to flick the switches quick enough so he decided to take another approach.

He leapt onto the hood of the vehicle and clambered to the driver side door, he prized it open easily only to be met with a laser gun pointed at his head. He dodged the first few bullets before kicking his bottom half into the truck effectively crushing the Kraang droid and took a hold of the wheel.

He flipped a lever causing the truck to speed up, he spun the wheel and crashed the truck into the control panel.

The portal switched off.

He cheered in his head and smiled. His brothers were safe along with the rest of earth.

''AAAAARRRHGHHGHG'' The little pink Kraang squealed angrily as it leapt onto Donnie's head, the poor turtle let out his breath in surprise as he fell out the truck onto some rubble below.

Donnie threw the Kraang off in alarm as he found he couldn't breathe, he knew this was going to happen but it had never really occurred to him that suffocating might hurt.

And hurt it did.

He was heaving, his throat raw and his chest tight. It felt as if his lungs had been grabbed by a giant fist that was squeezing with all its might.

He writhed on the floor as the five Kraang stood over him, his vision darkened as they grabbed him and hauled him up.

He woke to the sound of something draining.

His body felt wet and warm. He could breathe?

He opened his eyes to find himself in a dark tube, there was still some green liquid running down the glass.

Was that what he was covered in?

He jumped as the tube opened to reveal two Kraang looking at him, they pulled him out and placed him on his feet.

Donnie tried to take a step back but slipped from the liquid.

''Wh-What happened?'' he growled. ''Why can I breathe?''

''Welcome'' The Kraang nodded. Donnie frowned, why did this Kraang make sense?

''You don't talk like the other Kraang'' Donnie observed.

''I am one of the head Kraang, I actually made an effort to talk English properly''

'' 'Talk English'?'' Donnie sneered. ''You mean speak English. You might wanna practice a bit more''

''You have been suspended in a life-saving liquid for two months thanks to me'' The Kraang retorted. ''You should've died''

''What do you mean life-saving?'' Donnie asked as he glanced between the two Kraang, ''Can he talk properly too?''

''No he's mute'' The Kraang replied. ''His punishment for being so useless. Anyway, our solution was life-saving because you were suffocating, slowly being throttled by our air so the mixture saved you by seeping in through your skin and into your bloodstream. From there it was carried to your lungs where it started the mutation so you can breathe our air.''

''Y-You mutated my lungs?'' Donnie swallowed thickly. ''Does that mean I can't breathe oxygen anymore?''

''Why would you need to? You're not going back to your world'' The Kraang chuckled. ''We're gonna need you''

''Why?'' Donnie asked fearfully, he tried to back away but the mute Kraang grabbed him and held him still.

''You are a being of earth, we've never had this opportunity before.'' The Kraang shrugged as he also grabbed Donnie.

And so Donnie's year of torture and misery began, the first month wasn't so bad as he was put to sleep for most of it but after a while they wanted to see how high his pain tolerance levels were and stopped using drugs.

He was tested on and changed.

Now not only could he breathe Kraang air but now water ran off his skin like water off a duck's back. Bits of his bones were broken and replaced with metal to strengthen his limbs and joints, the top quarter of his shell had been broken, cut and re-shaped so it resembled sharp spikes.

But worst of all was what happened on his last day.

He had been desperate, blind.

He had made a dash for the door in hopes of escape only to be caught.

His punishment was severe.

His legs, from below the knee down, were cut off with a blunt saw.

How he had screamed and begged.

He had cried and howled.

But it was all for nothing.

Soon enough he felt something white hot burn both wounds to seal the injuries, to prevent him bleeding out and dying.

They had left him there to wallow in his pain and misery.

Donatello refused.

He had dragged himself over to the table where he found various pieces of metal that didn't even exist on earth, they were flexible and bouncy.

Perfect replacements.

And so he created his own running blades and escaped his prison.

Once he was out he spent months trying to fix what had been done to him. He managed to snap his spikes off his shell and file the sharp edges down into a smooth curve.

He was just giving up after two years, eleven months and 25 days of being away from home when suddenly he had heard familiar voices.

He had ran to them, faster than he had ever run in his life.

''-It might've been more than two years! Who knows how long it's been!''

He grinned and was quick to engage.

He finally found his brothers, they were finally reunited.

* * *

 **Please Review x**


	10. Chapter 10

**Wow... I have been gone for a while! sorry guys! How are you all?**

 **Seriously sorry that I haven't updated, hope you enjoy xx**

* * *

 **Betrayal and Guilt**

''So yeah'' Donnie sighed, his brothers looked sick. ''That's what I've been up to''

''All that happened in the space of two hours!?'' Leo blanched.

''Two years… almost three, Time moves differently here'' Donatello shrugged.

''Just said that dude'' Mikey sighed as he shifted slightly, he wasn't sure what to do.

''I'm gonna kill every Kraang out there'' Raph promised as he turned away from his brothers to look out over the floating islands. ''They won't get away with this''

''Raph, you guys have no time for that'' Donnie grabbed Raph's arm and lead his three brothers into the lab. ''You guys have got to get back to earth before your oxygen runs out''

''We can't'' Leo replied hastily. ''We can't leave you behind, you're our brother. We're a team''

They entered the huge room and stared up at the massive pulsing portal.

''The portal is of no use now'' Donnie rubbed his arm. ''I doubt they'll keep it open for long…''

''Maybe whatever they used makes your lungs adapt?'' Leo suggested hopefully.

Donnie frowned, Leo could be right. Maybe he would go through and be able to breathe?

But if he was wrong…

He'd die.

Was it a risk worth taking?

Donatello looked at each of his brothers, they didn't have long left.

They wouldn't leave without him.

A sudden thought came to Donnie's mind.

''Wait a minute…'' He frowned, his brothers cocked their heads. ''How do the Kraang breathe on earth?''

''is that really what you should be focussing on right now?'' Raph snapped irritably.

''If you want me to come back with you and survive then yes'' Donnie responded coolly, ''I breathe the same air as them now, so how do they go around earth and still manage to breathe?''

''Maybe it's those suits?'' Mikey shrugged.

''Maybe'' Donnie nodded. ''How was the lab when you left?''

''uh… what do you mean?'' Leo asked confused.

''Was it still operational?'' Don elaborated. The three brothers looked at each other and nodded.

''yeah?'' Raph answered uncertainly, ''Why?''

''I can try going through… if I can breathe then that would be great but if I can't'' He took a deep breath. ''If I can't… I will have to try and find a way to breathe before I suffocate, if that lab is fully functional then there may be something I can access easily that will help me breathe after that all I need to do is find a way to fix myself''

''is that all?'' Raph asked sarcastically, Leo rolled his eyes and stepped towards Don.

''Are you sure you'll have enough time to do it?'' He asked worriedly.

''um… Not really 100% sure but… it'll be fine'' Donnie blushed before shaking his head. ''But I'll need you guys' help, when I start suffocating I'll panic. You need to make sure I stop pretty quickly otherwise we won't have enough time''

''Of course'' Leo nodded. ''And we'll need to keep the Kraang away.''

Donnie nodded.

''We can do this'' Leo assured his brothers. ''We going?''

Raph and Mikey nodded as Donne sighed.

''Let's go''

Together the four brothers leapt through the portal back to their own dimension.

* * *

 **Please Review x**


	11. Chapter 11

**Hey everyone! This chapter's a little longer than yesterdays but it's still a little short, I don't have much time at the moment but I hope it's ok!**

 **Enjoy x**

* * *

 **Betrayal and Guilt**

The four turtles landed in their own dimension easily, the kraang had been waiting for them and now stood with their lasers pointing at them.

Leo, Raph and Mikey began the attack while Donnie surveyed the room, he was holding his breath for now. He knew he still needed to dispose of the portal which should be pretty easy this time seeing as they had been in a rush to start it up again.

He went straight for the control panel and smirked at the shabby wiring, they really must've been desperate.

With a flick of his wrist the portal was shut down, Don grabbed a weirder, more alien version of a wrench and started smashing the consoles. This would set the Kraang back for years or at least until they were ready to deal with the threat properly.

Three of the kraangs were down but there were still three left. The rest of the building seemed to have evacuated leaving just the few of them in the room.

Leo was happy that everything seemed to be working efficiently but was worried for Donnie, his brother was still holding his breath and none of them were ready to deal with whatever would happen when he tried to breathe.

These musings had distracted Leo too much, he realised his kraang was pointing his gun at Donnie's shell.

''DON! MOVE!'' Leo commanded as he barged into the alien robot. The kraang still shot but Donnie managed to jump out of the way in time. The shot blew up the console.

This should've been a good thing but unfortunately the blast had caused Donnie to release his breath.

He gasped hoping that he would be able to breathe only to find the oxygen was stinging his lungs. He coughed and spluttered as he tried to concentrate.

The oxygen was poisonous or something, he wasn't sure why it hurt so bad all he knew was that he was breathing it in enough to survive.

''DONNIE!'' Mikey yelped as he ran towards his choking brother.

Raphael and Leonardo took out the last two Kraangs and were quick to join their little brothers.

They grabbed at their choking sibling, hoping that their touch would soothe him.

''Calm down… calm down Donnie'' Leo hushed as he patted his brother. ''Think through it, c'mon… we need to find something to help you breathe''

Donnie shook his head as he fell to his knees, he could feel his lungs pulsating beneath his ribs. He could feel them moving about within him.

This wasn't normal. This wasn't him suffocating.

He was dying and he didn't understand what was going on inside his body.

Technically he was breathing though so he decided he needed to tell his brothers of the problem.

He went to talk but gagged instead, he felt a thick, warm fluid rise up from his throat and spill out over his chin and onto the floor.

Blood.

''Shit'' Raph cursed as the brothers stared at the growing pool of red. ''Leo, what do we do!?''

''I- I don't know… this is really bad!'' Leo stressed. Donnie spat out more blood.

''N'thin… you c'n do'' Donnie gurgled as he swayed, honesly he was starting to feel a little dizzy.

''What?'' Leo shook his head. ''There's gotta be something!''

'''m n't s'fficatin' 'm bein' poisned'' Donnie mumbled before coughing, blood flecked them all but nobody cared.

''the fuck?'' Raph asked as he looked at his brothers. Donnie gave a shout as he fell onto his side, he was writhing and groaning. His brothers had never been more scared, what were they going to do!?

Donnie had never experienced pain like this before, he could literally feel his lungs moving and contracting within him. He wondered how long it would be until he passed out or died, he hoped it would be soon.

Suddenly his lungs jolted and blood sprayed from his mouth. He curled up onto his side as he trembled.

His throat felt clear and he realised he was breathing, he was actually breathing oxygen. Nothing had ever felt sweeter.

He opened his eyes as he breathed deeply, calming himself and his brothers who were kneeling around him.

He slowly sat up and gripped his chest in pure shock, his lungs adapted… his lungs had actually been changing and mutating within him.

''D-Donnie?'' Mikey whimpered. Donnie looked up to see his brothers pale, blood flecked faces staring back a him with loving concern.

He gulped and threw himself onto his brothers in a hug, they were quick to hug him back. That had been too close.

''I-I'm ok'' Don rasped,

''Thank god'' Leo breathed. ''That was terrifying''

''What the fuck was that?'' Raph asked terror still lacing his voice. ''What the hell happened to you?''

Donnie pulled back as the realisation of what happened struck him, he bent to the side away from his brothers and barfed onto the same puddle of blood that he had spat out only minutes ago.

He heaved until nothing would come up and promptly fainted. As he fell he felt his brothers stop him before he could land in his own puddle, he felt them lift him up and start walking as he let darkness consume him.

* * *

 **Please Review x**


	12. Chapter 12

**Hey guys, sorry this took so long! Fanfiction hasn't been letting me upload chapters because apparently they're the wrong file even though nothing has changed. Anyone else having this problem or have any idea on how to fix it? would appreciate the help, copying and pasting is super tedious.**

 **Also I have heard about what happened in Orlando. I hope all of you are safe, I hope everyone in your family and friends are all safe too.**

 **Here's the chapter x**

 **Enjoy x**

* * *

 **Betrayal and Guilt**

Donnie felt cold.

That was the first thing he was aware of.

His chest ached as if his ribs were too big for his plastron, he could feel a pair of arms holding him and swaying him from side to side.

What happened?

He remembered leaving dimension x, his brother had came for him…

They had destroyed the portal.

And he had tried to breathe?

Oh god.

Donnie's eyes shot open as he leapt out of whoever's arms, he landed on all fours as he panted.

He remembered the feeling of his lungs moving in his chest, blood rising in his throat only to pour onto the floor.

The sick dripping of red from his chin.

''Donnie! It's ok… you're ok!'' came a familiar voice from his right, he opened his eyes to find his brothers knelt around him as he pushed away his panic.

He nodded to them as he straightened up, he put an arm around his chest automatically.

''Sorry'' He breathed. ''uh… about now and what happened back in the kraang lab''

He could see his brothers and himself were still stained with his blood.

''What happened back there?'' Leo asked in concern. Donnie noted that he had been the voice from earlier.

''M-My lungs… they mutated to breathe our air'' Donnie gulped and forced himself to breathe slowly. ''And I felt every second of it''

The brothers looked at one another in horror.

''Dude'' Mikey cringed. ''Gross''

''Yeah'' Donnie smiled tiredly. ''really gross''

''Is it… y'know'' Raph shuffled awkwardly as Mikey hugged Don, ''Ok now?''

''I'm breathing if that's what you mean'' Donnie replied dryly. ''And I'm not dead''

The brothers rolled their eyes and Donnie knew they wanted a real, honest answer.

''It aches a little'' He nodded as he removed his arm from his chest, Mikey released him and frowned. ''But… I think I'll be ok?''

''You think?'' Leo frowned. ''That doesn't give me much confidence''

''I don't know til I've tested myself'' Donnie shrugged as he shakily stood up, his brothers followed suit.

Donnie looked at the New York skyline he had come to know and smiled. It was good to be home.

He rolled his shoulders as he thought about his scars and shell, they would be fine. He looked down at his makeshift legs and sighed, they may be more of a problem.

''Hey'' Mikey nudged him softly. ''What's wrong?''

The brothers followed Donnie's gaze and their expressions softened.

''I guess… technically, I'm disabled'' Donnie mused.

''So?'' Mikey kicked the running blades gently. ''Since when has that stopped anybody? Loads of people are disabled, that doesn't change how awesome they are!''

''Having a disability is not something to be ashamed of nor is it a bad thing'' Leo put a hand on Donnie's shoulder. ''You're still alive… that's all that matters to me''

''How am I gonna be a ninja with no legs?'' Donnie growled.

''Now yer exaggerating'' Raph sniggered. ''You have the top halves and your knees. Besides, it's not like you haven't built new ones!''

He motioned to Donnie's running blades, Donnie shuffled slightly and nodded.

''I guess…''

The brothers smiled before looking out over New York again.

''Lets go home'' Leo nodded happily. ''we've done enough for today''

''Woah!'' Mikey grinned. ''We were out for four hours! Sensei's gonna freak!''

''Feels like I've been gone longer than that'' Donnie smirked. ''Feels like I've been gone for years''

He frowned as his three brothers look away in shame, he realised that they felt bad for what had happened to him and that joke was salt in the wound.

''Hey'' He chuckled as he jogged forward and jumped to the next rooftop. ''You guys comin' or what?''

His brothers grinned as he spun round and sprinted away and quickly joined him.

The brothers arrived back at the lair to find their father pacing in the pit with a cell phone in his hand, the brothers looked at one another before pulling their cells out of their belts.

All three were broken.

They looked at Donnie expectantly and he shrugged, he didn't have his anymore.

''I'll fix them'' Donnie promised. At this their father's ears pricked up and he spun around the face them.

''My Sons!'' He gasped as he rushed towards them, ''What happened? Are you four alright? Why didn't you answer my calls?''

He froze when he caught sight of their appearances, especially Donnie's.

''What happened!?'' He gasped.

''Long story'' Leo sighed. ''Really long story''

''Come'' Splinter motioned for his children to sit in the pit, they did so gladly. Splinter knelt before them. ''Tell me your story.''

And they did.

Each took a turn and Donnie filled in on the bits only he knew about, he decided to keep the details of his lungs mutating to himself and told them he wasn't 100% aware of anything during the mutation.

The brothers knew he was lying but understood why.

Splinter listened patiently and once they were done he stood up without a word and left the room.

''Do ya think he's mad at us?'' Mikey whispered worriedly, the brothers shrugged equally as confused and worried.

Master Splinter returned with a basin of warm soapy water and four sponges, towels and blankets, along with these he had his large first aid kit tucked under one arm.

The brothers gaped at their father's ability to carry it all without anything falling to the floor.

Splinter placed the basin in front of his sons and handed each of them a sponge.

''You three clean yourselves up, I wish to give Donatello a look over first'' Splinter commanded gently, the brothers did as they were told.

''Master'' Donnie began, he knew he had been more injured than his brothers but did not want his father to see what the kraang had done to him, especially seeing as all that was left was scars.

Splinter said nothing and merely put a hand on Donatello's shoulder.

First he looked over the front of his sons body, there were many scars but no open wounds anymore. His eyes hovered over Donnie's knees as he placed his other hand on the cool metal below the left one.

Donatello flinched slightly but said nothing.

Master Splinter then, gently, pulled Donnie's shoulder so the turtle would shift enough for Splinter to see his shell.

The brothers peaked but winced then they saw how much of it their brother had filed down, there were a lot of nerves in their shells and filing them was always an uncomfortable experience.

It didn't have to be done often, only if they lost a part of their shell that left sharp corners.

Master Splinter placed a hand on what was left of the top half of the carapace, Donnie closed his eyes in shame.

''There are no wounds we can heal on your body'' Splinter sighed as Donatello turned back around to face his father. ''But there are a couple within your mind that we can fix easily if we are together''

Donnie blinked in surprise but smiled weakly.

''You think?'' He asked quietly.

''Yes.'' Splinter nodded. ''You have been through much but now that you are safe-''

''But what about my lungs?'' Donnie interrupted suddenly. ''I- um… I don't know how stable they are…''

Splinter frowned as he thought about this.

''I do not see why they wouldn't be stable'' He replied calmly. ''They were stable while you were in dimension x and they are stable just now. This mutation could be very useful to you if it can help you adapt to breathe in different environments''

Donnie frowned as he nodded.

''I guess…''

Splinter nodded but knew Donatello would not dismiss the issue so easily.

''Clean up'' Splinter nodded as his other three sons put their sponges back in the water. ''I must call April, she was very worried about you''

The four brothers cringed as Splinter went to the dojo.

Donatello used the sponge to gently clean his plastron as his brothers looked at him.

''I forgot about that'' Mikey winced.

''Same'' Donnie replied without looking at them.

''We're still sorry'' Leo sighed. ''We caused all of this and-''

''No you didn't'' Donnie snapped. ''I made my own decisions when it came to the kraang and I've already forgiven you for being mad at me.''

The brothers looked a little shocked at his outburst so Donnie took a deep breath.

''Look, I completely understand why you guys were afraid of losing me to April… When I was in dimension x I experienced the loneliness of not having a team member around and it sucked… we're brothers you guys, I don't ever want us to be split up'' Donnie looked up at his brothers shyly. ''I love you guys way more than I will ever love April.''

Leo smiled, he and his brothers had come a long way and now he knew there was no reason to worry.

''We've known this from the start'' Leo nodded as Donnie began cleaning himself again. ''We were just too blind from jealousy to see it…''

The brother smiled at one another for a moment.

''Anyway'' Donnie snapped out of it, ''Will you guys get my shell? I can't reach back there and I'm pretty sure it's covered in kraang germs''

The brothers chuckled as they grabbed their sponges.

''That sounded so gross'' Mikey stuck his tongue out. ''It's been a weird day huh bros?''

''You said it'' Leo yawned.

''About the lungs'' Raph coughed. ''Are you gonna check them out? Make sure everything's ok?''

''Yeah… I will eventually'' Donnie shrugged. ''Once I'm feeling a little less tired. I'm gonna work on some new running blades too, these ones are too kraangy for my liking''

The brothers laughed.

Finally, all seemed well again. The family were all back together and nothing, after all they've been through, can tear them apart.

* * *

 **Only one more chapter left, I'll hopefully post it up later today so look out for it.**

 **If you can help with my little problem then please do!**

 **Leave a Review xx**


	13. Chapter 13

**This is the last chapter guys! I don't know what my next story will be but i hope you guys will stick around to read it. Thanks so much for reading this all the way through and for showing your support!**

 **Enjoy x**

* * *

 **Betrayal and Guilt**

Leo, Raph and Mikey were hiding on the rooftop as they looked down at their brother in the alley, they were lying in wait.

''C'mon'' Raph growled as he narrowed his eyes. ''C'mon''

''Be patient Raph'' Leo soothed.

''You guys still haven't told me what to do'' Donnie muttered into his comm.

''Relax bro'' Mikey grinned. ''You'll know it when it happens''

Suddenly a shape appeared in the mouth of the alley.

''Uh oh'' Mikey ducked down a little further.

''Begin phase one'' Leo whispered. ''Step forwards a little… lure her in''

''Go on Donnie'' Raph nodded quietly. ''And keep her from looking up here''

''It's too dark for her to see us anyway'' Leo shushed him. ''Back up team… stay ready''

Raph and Mikey nodded.

The shape headed towards Donnie slowly as Donnie stepped forward.

''Get ready'' Leo warned. ''Anything could happen''

''Not giving me a lot of confidence guys'' Donnie muttered moodily.

''Smile man! Smile!'' Mikey stressed, Donnie smiled slightly and the shape seemed to relax.

''Hey'' Donnie smiled as the shape got closer.

''SH!'' Leo shushed hurriedly. ''You don't wanna be the first to engage… let them come to you''

''Hey'' The shape replied as she stepped up to Donnie. ''Sorry I'm late, I couldn't decide what to wear''

April stood before him wearing her long, red hair down so it rippled over her shoulders and down her back. She wore a small ocean blue dress and a purple shawl around her shoulders.

''Tell her she chose well'' Leo whispered.

''Tell her she looks pretty and you're happy to see her!'' Mikey chirped.

''Nah man! Just ask her how she is'' Raph scoffed.

''You look great April'' Donnie smiled fondly. ''You're beautiful''

''Or just go with that'' Leo shrugged. ''That works too''

''Thanks D'' April giggled. ''How is everything? Y'know… back home and stuff?''

''It's all good'' Donnie smirked, he had told April everything that had happened over the last week and she had understood completely. She had watched his breakdowns and tried to help the family to the best of her ability during this tough time, everything seemed to be going well and Donnie was well on his way to recovery.

''I'm glad we can finally go out'' April chuckled, she looked down at Donnie's legs. ''Those new?''

''Yeah… I made 'em yesterday'' Donnie grinned as he looked down at the green metal running blades. ''They're so much better than my first ones''

''Stop rambling!'' Leo commanded.

''I'm not! It's called small talk!'' Donnie mumbled.

''Sorry?'' April asked with a frown, ''Did you say something?''

''This is what happens when you sass us'' Raph smirked.

''Abort! Abort! It's all over!'' Mikey whispered.

''No, he can come back from this'' Leo replied. ''Just say 'nothing' coz it doesn't matter!''

''Doesn't matter'' Donnie waved her off. ''Shall we go?''

''yeah just give me one sec'' April smirked as she reached forward and pulled Donnie's comm out from within his ear.

Donnie froze, as did his brothers.

April tucked the device into Donnie's belt.

''I'd like to go on a date with just you if you don't mind'' She giggled as she took Donnie's hand in hers, ''You'll do better without them anyway''

Donnie chuckled in embarrassment.

''BYE GUYS!'' April called up at the brothers. ''WHEN WE CLIMB UP THERE YOU'D BETTER BE GONE!''

Donnie smirked as he watched the silhouettes of his brothers zip away hurriedly.

''Shall we?'' He grinned.

''Let's go!'' April nodded happily.

And with that they leapt up onto the rooftops and bounded away under the stars.

Donatello was not completely healed but it was a start. His brothers were there every minute to help him through his breakdowns over the memories of his torture, they had earned their right to forgiveness and Donnie knew he couldn't stay mad at a family member.

Everything was finally falling into place and Donnie was truly happy.

* * *

 **Please leave a review and I'll see you in whatever i write next! xx**


End file.
